Exam 18: Soils and Chemical Pollution

In the design of a _______ type landfill, evapotranspiration by cover vegetation should be maximized.

Anaerobic decomposition of organic wastes in landfills results in the production of ______ gas which is often recovered and used.

Generally an organic chemical is destroyed when it is lost from the soil by volatilization.

Hyperaccumulators are plants that ________.

In the design of a _______ type landfill, biodegradation and colloid adsorption are important mechanisms of reducing pollution potential.

The United States Environmental Protection Agency regulates the amount of sewage sludge that can be applied on agricultural land by setting limits on ____.

Soil properties play a much more important role in choosing a site for a containment-type landfill than for a natural-attenuation-type landfill.

Which of the following are considered to be "heavy metals" that can contaminate soils and the food chain?

Draining a chromium-contaminated wetland would be likely to immobilize the metal so that environmental chromium toxicity problems would be minimized.

A soils contaminated with a heavy metal may be bioremediated by ____.

The principal human health effect of exposure to radon is ____.

In the United States between the 1970s and the 1990s, the level of heavy metals found in municipal sewage sludge ______.

Radionuclides from nuclear power plant accidents and weapons testing pollution get into the food chain primarily by _____.

If a soil is repeatedly polluted by a toxic organic compound over a period of years, the soil microbes will lose their ability to degrade the toxin.

Soil application of certain pesticides reduces the diversity but increases the numbers of soil mesofauna.

In soils treated with excessive rates of high-metal sewage sludge, most of the cadmium and lead is likely to be found in the form of exchangeable ions on the clay and humus exchange complex in the soil.

Soil washing is a commonly used method of bioremediation.

Bioremediation of contaminated soil involves the use of _________ to ameliorate the soil pollution.

Of the following metals often found in sewage sludge, which would most likely become toxic to farmers' crops if sludge applications exceeded the recommended amounts.

Organic chemicals whose structures have positively charged groups tend to be very immobile in the soil.